Solderless wire connectors utilizing slotted flat plate contact members like that of the present invention have previously been described, for example, in Levin et al., U.S. Pat. No. 3,012,219 and Elm, U.S. Pat. Nos. 3,258,733 and 3,388,370. These connectors provide excellent electrical contact with insulated wires of appropriate diameter when only one wire is placed in each slot of the flat plate. Usually this presents no problem since the flat plate contact members are provided with multiple slots for multiple wires to be connected together. However, some applications, such as the wiring of miniaturized electronic circuits, do not permit the space for multi-slotted contact members.
Multiple wires can only be reliably connected in a single slot of a flat plate contact member if the slot tapers from its open end toward its closed end. Such tapers can be effectively stamped in the flat plate when the slots are for relatively large diameter wire, and such taper slots have been stamped to make positive connection even when only a single wire is to be connected in one slot, as shown in U.S. Pat. Nos. 3,511,921; 3,718,888 and 3,899,236. Flat plate contact slots have also been made to taper by stamping of a parallel edge slot and then twisting the legs of the contact, as illustrated in U.S. Pat. No. 3,820,058.
Stamping of slots in flat plate connectors is, as a rule of thumb, limited to a slot width no less than the thickness of the flat plate material. See, for example, U.S. Pat. No. 3,824,527 at Column 3, lines 33 through 52. It has also been found that it is generally impractical to make free-standing flat plate connectors of a thickness less than 0.010 inch because if a lesser thickness is used the legs of the contact tend to distort out of the plane of the flat plate and not make effective electrical contact with the wire. However, in wiring miniaturized electronic circuitry it is desirable to connect wires of 30 AWG and smaller having a diameter of 0.010 inch and less, thus requiring a slot with less than that readily available by stamping. This problem of stamping narrow slots becomes even more severe if it is desired to taper the slot. The prior art has not provided any narrow width tapered slot or any other effective means for connecting a plurality of small diameter insulated wires with a single slot flat plate contact.